we'll be doing that over the week any time the temperature is over 90 degrees. >> reporter: metro also wants riders to be comfortable during travel. maintenance crews have been focusing on so-called hot cars, railcars with air conditioning problems. >> we would consider a hot car a health issue and we want to take those cars out of service. we strategically deployed car may not techs all around the system. >> reporter: back out live in bethesda, it wasn't long ago, a couple hours ago, there were some escalator issues here at this station. everything has been fixed and earlier today at the foggy bottom metro there were some problems, but it really wasn't a mechanical issue, shawn, instead a safety switch thrown and that caused the escalator to stop right before rush hour. metro officials are saying basically the escalator worked as it should. it shut off because it felt like something had happened. so automatically it shuts off until maintenance crews can come in, take a look and then start it up again.